1. Field of the Invention
The present invention relates to a broadcast receiver for receiving a broadcast of digital signals, a transmission control unit for controlling the transmission of the digital signals and a recording/reproducing apparatus for recording and reproducing the transmitted digital signals.
2. Description of the Related Art
Currently, MPEG (Moving Picture Coding Group) is in wide use as an encoding technology for digital TV broadcasting. In the case of an MPEG2 system, it is possible not only to multiplex video data, audio data and text data within a single program but also to multiplex and transmit a plurality of programs.
However, in a conventional receiver, only one demultiplexer which separates multiplexed signals is provided for transmitting signals to the MPEG decoder. Therefore, the conventional receiver is capable only of handling one program to be decoded and reproduced among m number of programs transmitted. That is, it is impossible, for example, to select and record on a VTR an n number of programs among m number of programs (m and n each is an integer satisfying m.gtoreq.n), or to select n number of programs and supply the corresponding data to a personal computer for processing.
The present invention is intended to solve these problems, and its objective is to realize a broadcast receiver capable of, while decoding one program among m number of programs, recording a plurality of other programs on a VTR or supplying data for other programs to a personal computer.
Furthermore, the development of a fast digital interface for performing an isochronous transmission of digital signals is recently in progress. Particularly, a serial bus of IEEE 1394 standard provides advantages of performing a transmission at a high rate and performing isochronous transmission and asynchronous transmission at the same time. Consequently, this serial bus is expected to serve as an interface suitable for multimedia transmission such as image data transmission. This interface is also expected to be adopted in a transmission control unit for transmitting data from the broadcast receiver mentioned above to a recording apparatus.
When the recording apparatus connected to the broadcast receiver records digital signals, in order to match the output timing of each data packet in the reproduction with the arrival timing of each data packet in the recording, it is necessary to generate a recording timing for each data packet and to record the recording timing together with the corresponding data packet as recording time-stamp.
In a conventional configuration, in order to generate a recording time stamp, it is necessary to analyze the internal structure of the digital signal and extract information for recovering the operation frequency from the digital signal, thereby increasing the amount of hardware on the recording apparatus side.
The present invention is intended to solve this problem, and afford for providing a transmission control unit and a recording/reproducing apparatus which does not require analyzing the internal structure of digital signals.